Personal information management systems have enhanced personal communication. Many personal information management systems provide multiple capabilities and manage information for large groups of people. Some personal information management systems, for example, manage electronic mail, personal tasks, calendar appointments, journal entries, notes, and/or other information. Such systems often provide enhanced capabilities for certain sets of users, such as users having accounts with the systems. For example, some systems allow users in a certain set, which may be defined by a directory, to see the states of each other's calendars. Such viewing can be useful, for example, for figuring out the best time to schedule meetings. Typical personal information management systems, however, have limited functionality and their existing capabilities often introduce additional issues. For example, if one person sees an unoccupied block of time on another person's calendar, that person may try to schedule a meeting in that unoccupied block regardless of the other person's opinion of the time block's appropriateness for the meeting. Once a meeting has been proposed, however, it can be difficult for an invitee to decline the proposal knowing that the organizer has seen the free space on his or her calendar.